#include <REGX52.H>
#include <INTRINS.H>
void Delay1ms()		//@12.000MHz
{
	unsigned char i, j;
	int xs=20;
	for(xs;xs>0;xs--){
		i = 2;
	j = 239;
	do
	{
		while (--j);
	} while (--i);
	}
	
}

void main(){
	P2=(P2&0x1f)|0x80;
	P0_0=0;
	while(1){
		if(P3_1==0){
			 Delay1ms();
			while(P3_1==0);
			 Delay1ms();
			P0_0=~P0_0;
		}
	}
}